msm: mdss: Add plane alpha support

Clean up the blending rule to follow blend_op set from hwc.
Use modulate alpha for plane alpha when it is not 0xff.

Change-Id: Iad7217563bcae5e89fe8e50954494f6afdcb8e79
Signed-off-by: Mayank Chopra <makchopra@codeaurora.org>

1 files changed, 28 insertions, 0 deletions

diff --git a/include/uapi/linux/msm_mdp.h b/include/uapi/linux/msm_mdp.h
index 168bf154fde4..0ea775cff219 100644
--- a/include/uapi/linux/msm_mdp.h
+++ b/include/uapi/linux/msm_mdp.h
@@ -395,6 +395,33 @@ struct mdp_overlay_pp_params {
 	struct mdp_hist_lut_data hist_lut_cfg;
 };
 
+/**
+ * enum mdss_mdp_blend_op - Different blend operations set by userspace
+ *
+ * @BLEND_OP_NOT_DEFINED:    No blend operation defined for the layer.
+ * @BLEND_OP_OPAQUE:         Apply a constant blend operation. The layer
+ *                           would appear opaque in case fg plane alpha is
+ *                           0xff.
+ * @BLEND_OP_PREMULTIPLIED:  Apply source over blend rule. Layer already has
+ *                           alpha pre-multiplication done. If fg plane alpha
+ *                           is less than 0xff, apply modulation as well. This
+ *                           operation is intended on layers having alpha
+ *                           channel.
+ * @BLEND_OP_COVERAGE:       Apply source over blend rule. Layer is not alpha
+ *                           pre-multiplied. Apply pre-multiplication. If fg
+ *                           plane alpha is less than 0xff, apply modulation as
+ *                           well.
+ * @BLEND_OP_MAX:            Used to track maximum blend operation possible by
+ *                           mdp.
+ */
+enum mdss_mdp_blend_op {
+	BLEND_OP_NOT_DEFINED = 0,
+	BLEND_OP_OPAQUE,
+	BLEND_OP_PREMULTIPLIED,
+	BLEND_OP_COVERAGE,
+	BLEND_OP_MAX,
+};
+
 struct mdp_overlay {
 	struct msmfb_img src;
 	struct mdp_rect src_rect;
@@ -402,6 +429,7 @@ struct mdp_overlay {
 	uint32_t z_order;	/* stage number */
 	uint32_t is_fg;		/* control alpha & transp */
 	uint32_t alpha;
+	uint32_t blend_op;
 	uint32_t transp_mask;
 	uint32_t flags;
 	uint32_t id;